New approach to electron microscopy imaging of gel nanocomposites in situ

Abstract

Characterization of Au-nanocomposites is routinely done with scattering techniques where the structure and ordering of nanoparticles can be analyzed. Imaging of Poloxamer gel-based Aunanocomposites is usually limited to cryo-TEM imaging of cryo-microtomed thin sections of the specimen. While this approach is applicable for imaging of the individual nanoparticles and gauging their resolution, yet dispensing dense gel-based samples onto electron-transparent substrates remains challenging. We show that Poloxamer gel-based Au nanocomposites exhibiting thermoreversible behavior can be imaged in a fully hydrated state using a commercially available fluid cell holder, and we describe a specimen preparation method for depositing femtoliter amounts of gel-based nanocomposites directly onto the 50 nm-thick SiN window membranes. Ultimately, fluid cell S/TEM in situ imaging approach offers a pathway to visualization of individual nanoparticles within a thick gel media while maintaining hydrated state of the carrier polymeric matrix.

New Avenues for Capturing Mineralization Events at Biomaterial Interfaces with Liquid-Transmission Electron Microscopy

“…Further, we are working toward exploring methods to probe the influence of surface chemical functionalization on Ti surfaces viewed in situ. For example, phosphoproteins are believed to be able to regulate HAP crystallization by controlling CaP nucleation versus inhibition in biomineralization systems and are thus strong candidates for surface functionalization in a biomimetic mineralization system. − Future work will determine methods for chemical functionalization, perhaps using the Protochips Shadow Mask System for reproducible drop-casting or exploring highly precise liquid functionalization methods, where surface patterning tools have been reported in the literature to be capable of depositing in a controlled fashion femtoliter amounts of gels on similar 50 nm-thick microchip membranes . Overall, this innovative research provides significant contributions to the development of liquid-TEM techniques for applications in materials and life science fields, paving the way for many exciting future avenues for in situ research.…”